The new feature, a "MiniStore" pane in the software, provides music recommendations to iTunes users based on the songs currently in the software's active playlist. To do so, it sends information about those songs back to Apple, even if the tracks weren't originally purchased from the iTunes Music Store.
The information exchange also includes a string of data linked to an iTunes customer's unique ID number, which is also used for other Apple accounts, such as the .Mac service and the Apple Developer Connection, computer experts found last week. An Apple representative said last week that the company did not store or archive any of the information from this MiniStore recommendation process.
Previously, that information exchange was not disclosed in any user agreement or in the software itself. However, an update posted late on Tuesday now prominently adds a notification inside the iTunes software itself when the MiniStore is turned on for the first time.
"As you select items in your library, information about that item is sent to Apple, and the MiniStore will show you related songs or videos," the note says. "Apple does not keep any information related to the contents of your music library."
The notification also provides a prominent new pointer to a button that will turn off the MiniStore, which does not exchange any information while inactive. As before, the feature can also be turned off by going to the menu of commands at the top of the software or by selecting a keyboard command.
The change has satisfied some of the critics who had emerged, even among committed Apple supporters, after the iTunes software release.
"I feel that Apple, in clearly telling users what the iTunes MiniStore does, has met its obligations for informing users," said Kirk McElhearn, an author of several Apple technical books, who helped identify the issue last week. "The fact that they clearly state, in this 'warning', that they do not keep any information about the contents of users' iTunes music libraries is sufficient for me."
Apple said it made the changes to assuage any potential consumer concerns.
"We've listened to our users and made access to the MiniStore an opt-in feature," Apple spokesman Tom Neumayr said.
